Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht 6229 EV, The Netherlands.
Maastricht Brain Imaging Center (M-BIC), Maastricht University, Maastricht 6229 EV, The Netherlands.
eNeuro. 2018 Apr 2;5(2). doi: 10.1523/ENEURO.0252-17.2018. eCollection 2018 Mar-Apr.
Sensorimotor integration, the translation between acoustic signals and motoric programs, may constitute a crucial mechanism for speech. During speech perception, the acoustic-motoric translations include the recruitment of cortical areas for the representation of speech articulatory features, such as place of articulation. Selective attention can shape the processing and performance of speech perception tasks. Whether and where sensorimotor integration takes place during attentive speech perception remains to be explored. Here, we investigate articulatory feature representations of spoken consonant-vowel (CV) syllables during two distinct tasks. Fourteen healthy humans attended to either the vowel or the consonant within a syllable in separate delayed-match-to-sample tasks. Single-trial fMRI blood oxygenation level-dependent (BOLD) responses from perception periods were analyzed using multivariate pattern classification and a searchlight approach to reveal neural activation patterns sensitive to the processing of place of articulation (i.e., bilabial/labiodental vs. alveolar). To isolate place of articulation representation from acoustic covariation, we applied a cross-decoding (generalization) procedure across distinct features of manner of articulation (i.e., stop, fricative, and nasal). We found evidence for the representation of place of articulation across tasks and in both tasks separately: for attention to vowels, generalization maps included bilateral clusters of superior and posterior temporal, insular, and frontal regions; for attention to consonants, generalization maps encompassed clusters in temporoparietal, insular, and frontal regions within the right hemisphere only. Our results specify the cortical representation of place of articulation features generalized across manner of articulation during attentive syllable perception, thus supporting sensorimotor integration during attentive speech perception and demonstrating the value of generalization.
感觉运动整合，即声学信号与运动程序之间的转换，可能是言语的一个关键机制。在言语感知过程中，声学-运动的转换包括皮质区域的募集，以表示言语发音特征，如发音部位。选择性注意可以塑造言语感知任务的处理和表现。在注意的言语感知过程中，感觉运动整合是否发生以及发生的位置仍有待探索。在这里，我们在两个不同的任务中研究了口语辅音-元音 (CV) 音节的发音特征表示。14 名健康人在单独的延迟匹配样本任务中分别注意音节中的元音或辅音。使用多变量模式分类和搜索灯方法分析感知期间的单次试验 fMRI 血氧水平依赖性 (BOLD) 反应，以揭示对发音部位（即双唇/唇齿与齿龈）处理敏感的神经激活模式。为了将发音部位的表示与声学协变分离，我们在不同的发音方式（即闭塞、摩擦和鼻音）特征之间应用了交叉解码（泛化）程序。我们在跨任务和单独的两个任务中都发现了发音部位表示的证据：对于元音的注意，泛化图包括双侧颞上和后部、岛叶和额叶区域的簇；对于辅音的注意，泛化图包含了右半球颞顶叶、岛叶和额叶区域内的簇。我们的结果具体说明了在注意的音节感知过程中，发音部位特征的皮质表示是跨发音方式概括的，因此支持了注意的言语感知中的感觉运动整合，并展示了泛化的价值。
